Quiet recording levels

Hi there, I’m fairly new to using recording equipment, and I have a problem I can’t seem to track down.  I recently got a PreSonus Firebox with an Audio-technica AT4040 condenser microphone.  I plan to use these on my iBook G4, primarily with Logic Express, but possibly with either Garageband 2 or the Cubase LE that came with the Firebox.  Here’s my problem: Whenever I’m monitoring my signal through the Firebox, the level seems very appropriate, even though it appears I have to turn the gain up on my mic a fair amount.  However, when I see the resulting level in my recording program (whichever it may be), the level barely breaks -25 dB.  Only when I turn the gain up nearly all the way on the Firebox do I get an appropriate level from my program, and I hear it clip on when I’m monitoring it through the Firebox.  I suppose I’m confused on a number of fronts–I’ve applied the phantom power to the mic as instructed by manuals, but my level meters in the programs still seem too low.  So, either the Firebox monitoring is right, or the program’s monitoring is, and I can’t figure out which.  I feel like there’s something I didn’t do in the Firebox or somewhere along the line, since the problem happens throughout each of my programs, on two different computers (I tried it on my Windows machine–same result).  Any thoughts from anyone would be much appreciated.

I haven’t personally used the Firebox, but I just checked out the product page for it at Presonus.

How are you monitoring your signal?  And how are you determining that the signal level is “very appropriate” on the Firebox?

The firebox does not appear to have any type of input level meters at all, other than a “clip” indicator.  So, you really don’t know what the levels are without looking at the input level meters in the software you are recording into.  However, to make sure you are getting fairly hot levels, you can crank the gain on the microphone until you see the “clip” light on the firebox just start to light up on loud signal peaks, and then back off of the gain just enough until the clip light doesn’t come on again (and maybe a little more for safety, since most people have the habit of performing a little louder once they really start recording).

If you are listening through headphones, maybe you just have the headphone level cranked way up, making you think the levels are appropriate when they are really kind of low.  Similarly, then, when you recorded at a decent level in the software and played back, they were clipping because the headphones were cranked and the headphone amp could have been clipping.

If you are monitoring through speakers, it’s not clear from the product page or the owner’s manual that I downloaded if the outputs on the back are professional +4, or consumer -10, level line outputs.  It’s says the outputs are balanced TRS, which typically would mean +4 professional levels, but it doesn’t say for certain.  So, the problem could be that if you are connecting the main outputs to a consumer stereo amplifier (with the RCA type input jacks typical of consumer electronics), then you may be feeding a -10 input with +4 professional level outputs, which would definitely cause clipping very easily.  If this is the case, you are going to have to use the DSP mixer on the fireface to reduce the monitor level to where it’s not clipping the input (or simply keep the volume knob low all the time).

The Firebox has its own internal software mixer to allow you to set up a mix of its inputs as well as outputs from your software for monitoring purposes without latency.  BUT, those levels in that DSP mixer have nothing to do with the levels of the signals you are recording going into the computer… the mixer is for monitoring only.  It appears from the screenshot of the DSP mixer that each channel, and the master fader, are attenuate only since the top of the scale is 0dB (unity gain)… so, if they implemented that the way it appears, it should not be possible to add additional gain to what you are monitoring which could cause clipping.  However, if you are mixing several signals together, such as what you are trying to record as well as playback from the computer, then the combination of those two signals could cause clipping in the monitoring output.  Or, as mentioned in the previous paragraph, if you are driving a consumer, -10 line level input, from a professional +4 level balanced output, you can easily clip the input stage of your amplifier or powered speakers.

So, as long as the clipping light on the inputs of the firebox isn’t lighting up, you should be able to safely judge your recording levels with the input level meters in your recording software.  If you are hearing clipping, but not seeing it on the clipping lights or on the software input meters, then it’s probably something wrong in the output monitoring stage, as described above.  However, record some audio into the computer and then zoom way into the waveform level to see if it’s really clipping or not (if something clips hard, you should see the top of the waveform squared off).  You can also play back the track and see if the output or channel level meter in the software shows any clipping or not… again, if you are seeing no signs of clipping in the recording software, then it’s probably the output monitoring setup.

The other possibility is that you could actually be clipping the internal electronics of the microphone itself… but, if you are just doing vocals, or most normal sources, that’s fairly hard to do with something modern like the AT4040.  Also, if that was the case, you wouldn’t need to be turning up the microphone gain on the firepod very much at all because you’d be getting a ton of output from the microphone.

Anyway, without talking with you personally on the phone and trying to walk you through all of this, this is the best that I can do.

If you are still having problems after eliminating all the possible causes I mentioned, you might try contacting Presonus tech support.  It could also be possible that your firebox is defective, or you need new drivers, or something else.

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